The invention relates to security systems having sensors that communicate with a central control panel, and in particular to the testing and installing of sensors in such a system.
Sensors, for example smoke detectors, may include a test button that is pressed to determine whether the smoke detector is working properly (for example, that its battery is still sufficiently charged). In many systems, pressing the test button causes an alarm signal to be transmitted, which in turn is received by a control panel of the system. One problem with this test button is that the control panel in such a system is not able to distinguish between an alarm signal caused by the sensing of smoke and an alarm signal caused by the pressing of the test button.
To overcome this limitation, some control panels include a “test mode,” and when put in this “test mode,” received alarm signals are considered by the control panel to have been generated by a test of a sensor and not by sensing an alarm condition. But if the control panel is not first put in the test mode, the control panel falsely considers a received alarm signal generated by a test of a sensor to be an actual alarm condition. The control panel then dials up and contacts a remote monitoring station and notifies the monitoring station of an alarm condition, which in turn leads to the dispatch of the police or fire department.
In addition, fraud prevention controls commonly instituted in connection with the installation of a security system may require installers to provide proof that they have actually installed all sensors the homeowner has purchased. To provide that proof, the installers typically test each sensor by generating an alarm signal that the control panel will in turn transmit to the monitoring station. Before the installer does such a test, the installer telephones the monitoring station and notifies the station that a test is going to be conducted and the alarm signals that soon will be received are not actual alarms.
Currently, security systems do not contact a remote monitoring station except to report alarm conditions, conduct phone line tests, and to report armings and disarmings. As such, the control panel, in response to the receipt of an alarm signal and accompanying test indicator, will not contact the monitoring station, and pressing a test button will not provide an audit message that the monitoring station needs to have to know that a sensor has been installed. To overcome this limitation, in the case of smoke detectors as an example, an installer may carry a can of artificial smoke which is sprayed into the smoke detector to generate the transmission of an alarm signal without the test signal. The control panel considers such a transmission to be an actual alarm and notifies the remote monitoring station accordingly. The cost and inconvenience of such an approach makes it undesirable.